1. Field of the Invention
The invention relates to a method and apparatus for excessive mechanical shock feature extraction for overstress event registration in computer or electronic systems.
2. Background Art
In many cases, a computer server is used as a building block, for example, telco system integrators and defense electronics system integrators. When a computer server is integrated into a product, the whole product has to go through qualification and other tests where mechanical shock/vibration tests represent a significant challenge. When an integrated product fails a compliance test, it can be difficult to root cause the failure.
In most cases, no information about the instantaneous or cumulative stress/shock levels that the system was subjected to is available or readily provided. Therefore, there is a need for overstress event registration and cumulative tracking in computer systems.
Registering overstress events in computer systems presents a technical challenge. In more detail, installation of some sensor to register box level operational shock events has been limited due to limited dynamic range (low frequency cutoff of embedded accelerometers); limited storage/bandwidth capabilities for waveform time-domain monitoring; and extreme noisiness of the time domain data due to rotation of internal cooling fans. Accordingly, there are obstacles that prevent straight forward overstress event registration and cumulative tracking in computer systems.
Background information may be found in Huang, et al., “The empirical mode decomposition and the Hilbert spectrum for nonlinear and non-stationary time series analysis,” Proc. R. Soc. Lond. (A) 1998. Further background information may be found in U.S. Pat. No. 7,478,075 and U.S. Pub. No. 2007/0244843.